<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="js/vue.js"></script>
</head>
<body>
    <div id="app">
        {{fullName}}
    </div>
    <script>
        var vm = new Vue({
            el:"#app",
            data: {
                firstName: "zhang",
                lastName: "jiaxuan"
            },
            computed: {
                fullName: {
                    get: function () {
                        return this.firstName + " " + this.lastName;
                    },
                    set: function (value) {
                        console.log(value);
                        var arr = value.split(" ");
                        this.firstName = arr[0];
                        this.lastName = arr[1];
                    }
                }
            }
        })
    </script>
</body>
</html>